The average weight of 20 girls in a school was 52 kg. Two new students of weight 54 kg and 50 kg were admitted. The ratio of this new average to the old one is:
1 : 1
Given:
In a school, the average weight of 20 girls was 52 kilograms
Two new students with weights of 54 kilograms and 50 kilograms joined the school
Concept Used:
Average = Sum of elements / Number of elements
Calculation:
Total weight of 20 girls = 52 × 20
⇒ 1040 kilograms
After the arrival of the two new students, total weight = 1040 + 54 + 50
⇒ 1144
New average = 1144/(22)
⇒ 52 kilograms
Ratio = 52 : 52
⇒ 1 : 1
∴ The ratio of the new average to the old average is 1 : 1.
Important Questions from Average
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If the average of two numbers is 13 and the square root of their product is 12, then the difference between the numbers is:
If the average of 5 consecutive odd integers in increasing order is 11 , then the average of the last 3 of them is:
There are two sections A and B of a class, consisting of 38 and 42 students respectively. if the average weight of the students of section A is 55 Kg and that of section B is 32 Kg. find the average weight of all the students in the class.
